Sound-eliminating board

ABSTRACT

A sound-eliminating board including sequentially bonded sound transmissible top layer, rigid sound-eliminating middle layer, and elastic sound-eliminating bottom layer. The sound transmissible top layer allows sound waves to penetrate through it into the rigid sound-eliminating middle layer, which includes a plurality of checkered partitions to define a plurality of open-topped small compartments. Sound waves penetrated into the rigid sound-eliminating middle layer reflect repeatedly in the small compartments to result in energy dispersion and counterbalanced energy due to overlapped amplitude of reflected sound waves, and are finally eliminated. In case of any residual low-frequency sound waves that penetrate through the rigid sound-eliminating middle layer into the elastic sound-eliminating bottom layer, they are further eliminated in the bottom layer.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a sound-eliminating boardcapable of thoroughly capturing noises and internally repeatedlyreflecting sound waves penetrated thereinto to finally eliminate thesound waves through energy dispersion, overlapped amplitude, andcounterbalanced energy of the sound waves. Any low-frequency sound wavesare also absorbed in an elastic and porous layer of thesound-eliminating board.

[0002] Noises do harm to a person's eardrum and have negative influenceson the mental and physical conditions of a person who works or lives ina noisy environment for a prolonged time. Unfortunately, there are somany noise sources in our living environment, such as stereophonicequipment, traffic equipment, machinery in plants, construction sites,etc., that many people are constantly and seriously harmed by noises.

[0003] There are many commercially available products designed toprotect people against noises, such as noise barrier shields erected attwo sides of overhead roads to isolate noises by forcing noise waves toreflect from the barrier shields, and sound-eliminating boards made ofsoft fibrous material for use indoors. It is known that when a soundwave meets some barrier, a part of the sound wave penetrates through thebarrier while others reflect or diffract. Factors that determine apenetrating power of a sound wave include physical properties of thebarrier and a frequency of the sound wave. Given the physical propertiesof a barrier are fixed, the lower the frequency of a sound wave is, thehigher the penetrating power of the sound wave is. Generally, a softsound-absorbing material is not able to completely absorb sound waves.And, the rigid noise barrier shield does not absorb sound waves butreflects and diffracts them, and part of the reflected and diffractedsound waves propagate at a height over the barrier.

SUMMARY OF THE INVENTION

[0004] A primary object of the present invention is to provide asound-eliminating board that is able to treat sound waves of differentfrequencies and can therefore be used indoors and outdoors to thoroughlyabsorb sound waves and achieve the purpose of eliminating sound.

[0005] To achieve the above and other objects, the sound-eliminatingboard of the present invention mainly includes a sound transmissible toplayer, a rigid sound-eliminating middle layer, and an elasticsound-eliminating bottom layer being sequentially bonded into anintegral unit. The sound transmissible top layer allows sound waves topenetrate into the rigid sound-eliminating middle layer, which includesa plurality of checkered partitions to define a plurality of open-toppedsmall compartments. Sound waves penetrated into the rigidsound-eliminating middle layer reflect repeatedly in the smallcompartments to result in energy dispersion and counterbalanced energydue to overlapped amplitude of the reflected sound waves, and arefinally eliminated. In case of any residual low-frequency sound wavesthat penetrate through the rigid sound-eliminating middle layer into theelastic sound-eliminating bottom layer, they are further absorbed in thebottom layer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The structure and the technical means adopted by the presentinvention to achieve the above and other objects can be best understoodby referring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

[0007]FIG. 1 is a perspective of a sound-eliminating board according tothe present invention;

[0008]FIG. 2 is an exploded perspective of the sound-eliminating boardof FIG. 1;

[0009]FIG. 3 is a sectional view of the sound-eliminating board of FIG.1;

[0010]FIG. 4 is an enlarged view of the encircled area of FIG. 3; and

[0011]FIG. 5 is a perspective of a sound-eliminating board according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Please refer to FIGS. 1, 2 and 3 in which a sound-eliminatingboard 10 according to the present invention is shown. Thesound-eliminating board 10 mainly includes a sound transmissible toplayer 11, a rigid sound-eliminating middle layer 12, and an elasticsound-eliminating bottom layer 13. These three layers 11, 12, 13 aresequentially bonded together to form an integral unit.

[0013] The sound transmissible top layer 11 is a decorative layerpermitting sound waves to pass through it into the rigidsound-eliminating middle layer 12. When the sound-eliminating board 10is used outdoors, the top layer 11 may be made of a rigid material andprovided with densely distributed tiny holes 17. And, when thesound-eliminating board 10 is used indoors, the top layer 11 may be madeof the above-described rigid material with a plurality of tiny holes 17or a gas-permeable soft material, such as non-woven fabrics (not shown).

[0014] The rigid sound-eliminating middle layer 12 includes a pluralityof checkered partitions 14 that together define a plurality of small andopen-topped sound-eliminating compartments 15 on the middle layer 12.When a sound wave enters the sound-eliminating middle layer 12, itreflects many times in the sound-eliminating compartments 15, resultingin energy dispersion of the penetrated sound. Moreover, reflected soundwaves in the sound-eliminating middle layer 12 create an effect ofoverlapped amplitude of sound wave, resulting in counterbalanced soundenergy. That is, the sound is eliminated. The sound-eliminatingcompartments 15 may be designed to have a depth within a range from 1 to5 cm. When the sound-eliminating compartments 15 have an increaseddepth, they are more effective in eliminating a sound of high decibel.And, sound-eliminating compartments 15 having reduced depth are moreeffective in eliminating a sound of low decibel. The sound-eliminatingcompartments 15 on the rigid sound-eliminating middle layer 12 may havea uniform depth or have different depths in randomly assigned areas,depending on actual condition of sounds in a place where sounds are tobe eliminated.

[0015] The elastic sound-eliminating bottom layer 13 is made of anelastic material having densely distributed pores 16 therein. When soundwaves propagate among the pores 16, sound energy of these sound waves isabsorbed in the elastic sound-eliminating bottom layer 13. Sound wavesthat penetrate the elastic sound-eliminating bottom layer 13 arelow-frequency sound waves capable of penetrating through the rigidsound-eliminating middle layer 12. When the low-frequency sound wavespenetrate into the elastic sound-eliminating bottom layer 13, theycollide with one another in the pores 16 repeatedly to result in changedfrequency of sound waves and weakened sound energy. The elasticsound-eliminating bottom layer 13 finally absorbs residual sound wavesand eliminates sound. An example of forming the sound-eliminating bottomlayer 13 is to compress and thereby mold rubber granules, and pores 16naturally form among the compressed and molded granulated rubber.

[0016] The sound-eliminating board of the present invention ischaracterized in the rigid sound-eliminating middle layer 12, in whichsound waves reflect repeatedly to result in overlapped amplitude ofsound waves and counterbalanced sound energy to effectively eliminatethe sound.

[0017] In another embodiment of the present invention, it is possible toproduce a sound-eliminating board 10′ that includes only the soundtransmissible top layer 11 and the rigid sound-eliminating layer 12, asshown in FIG. 5, for use at a location where no low-frequency sound waveexists.

[0018] With the above-described structure, the rigid middle layer 12 andthe elastic bottom layer 13 of the sound-eliminating board of thepresent invention are able to eliminate high-frequency and low-frequencysound waves, respectively, making the present invention an excellentsound absorption material.

What is claimed is:
 1. A sound-eliminating board comprising a soundtransmissible first layer and a rigid sound-eliminating second layerbonded together to form an integral unit; said sound transmissible firstlayer being a decorative layer permitting sound waves to penetratethrough it into said rigid sound-eliminating second layer, and saidrigid sound-eliminating second layer including a plurality of checkeredpartitions that together define a plurality of small and open-toppedsound-eliminating compartments on said second layer.
 2. Thesound-eliminating board as claimed in claim 1, wherein said soundtransmissible first layer is made of a rigid material and provided witha plurality of densely distributed tiny holes.
 3. The sound-eliminatingboard as claimed in claim 1, wherein said sound transmissible firstlayer is made of gas-permeable non-woven fabrics.
 4. Thesound-eliminating board as claimed in claim 1, wherein saidsound-eliminating compartments on said rigid sound-eliminating secondlayer have a uniform depth.
 5. The sound-eliminating board as claimed inclaim 1, wherein said sound-eliminating compartments on said rigidsound-eliminating second layer have different depths in randomlyassigned areas.
 6. The sound-eliminating board as claimed in claim 1,further comprising an elastic sound-eliminating third layer bonded to alower side of said rigid sound-eliminating second layer opposite to saidfirst layer, and said elastic sound-eliminating third layer including aplurality of densely distributed internal pores.